Safety lock for coldrooms and like applications



B. STERNER Nov. 26, 1968 SAFETY LOCK FOR COLDROOMS AND LIKE APPLICATIONS 2 Sheets-Sheet l Filed June 19, 1967 ummm gena/MJ flume/z Znacmu WML.

B. STERNER Nov. 26, 1968 SAFETY LOCK FOR COLDROOMS AND LIKE APPLICATIONS 2 Sheets-Sheet 2 Filed June 19, 1967 Il l Il @ffl/491,941 /r/ r United States Patent O Mice 3,412,586 SAFETY LOCK FOR COLDROOMS AND LIKE APPLICATIONS Bernard Sterner, Paris, France, assignor to Societe Armetal, Saint Ouen, France, a French body corporate Filed `lune 19, 1967, Ser. No. 646,844

Claims priority, application France, June 29, 1966,

Ciaimsfl. 711-92) ABSTRACT OF THE DISCLOSURE A safety lock for a door for a coldroom and the like, comprising a keeper having a notch and rotatable in the door frame by means of a handle within the coldroom so as to shift the notch away from a bolt mounted on `the door and normally elastically biased into the notch for locking the door, the locking position of the bolt being controlled by a key barrel, so that the door can be unlocked from inside the coldroom even when the bolt has been placed in its locking position by the key barrel.

The present invention relates to a safety lock for coldrooms and like applications.

It is known that coldrooms employed in butchers shops or -food stores are provided with coldtight very thick doors. The closing of these 'doors with a key creates a riskabove all when it concerns very large coldrooms-of leaving a person locked in the room without a possibility of this person manifesting his presence inside the room and opening the door. Indeed, these doors have a very high sound insulation owing to their thickness and the locked-in person may die of the cold.

The object of the invention is to remedy this drawback.

The invention provides an improved lock for coldrooms or like installations, wherein the keeper consists of a member having a notch occupying a part `of the cross section of the member and co-operating with the bolt, the keeper being rotatable in the door frame by an arm located on the inner face of the door frame and thus enabling, by the rotation of the keeper, the notch to be withdrawn from the bolt carried by the door, so that the bolt assumes a position in which it bears against the unnotched part of the keeper, the bolt being biased by a return spring towards the keeper to a locking position in sai-d notch and combined with a lock-operating key barrel and comprising a recess which enables it to effect a lost-motion travel relative to the barrel `for withdrawing from the keeper.

A door supplied with such a lock can be opened fmrom inside the room closed by this door without the use of any key, even when the lock has been closed by means of a key from the exterior. Further, after having been opened in this way, it can be closed again without a key from the exterior without being locked, if the arm remains in the position which withdraws the notch, and can be locked by the key if this arm has been shifted back to its locking position.

Further features and advantages of the invention will be apparent from the ensuing description with reference to the accompanying drawings.

In the drawings:

FIG. l is a partial perspective view of a door equipped with a lock according to the invention;

FIG. 2 is a perspective view of a fixed plate for the lock shown in FIG. 1;

FIG. 3 is an elevational View of the lock, partly in section;

3,412,586 Patented Nov. 26, 1968 FIG. 4 is an elevational view of the lock from inside the coldroom, the lock being partly in section taken along the line 4 4 of FIG 3;

FIGS. 5 and 6 are perspective views of another lock according to the invention and the fixing plate for this lock respectively, and

FIG. 7 is a horizontal sectional view of the lock shown in FIG. 5.

In the embodiment shown in FIGS. 1, 2, 3 and 4, the loc'k comprises a housing 1 containing a bolt and means actuating the latter, this housing being fixed to the door P proper by means of a metal fixing plate 2 (FIG. 2) which is secured to the door by screws 2a. This fixing plate comprises a portion 2b which is adapted to reinforce the portion of the housing extending beyond the door and provide fixing means for the latter which are inaccessible when the door is closed. This portion 2b is provided with ya circular opening 2c for the passage of a keeper. The housing 1 is secured to the fixing plate 2 by the cooperation of a rod (not shown), xed to the housing, with a curved portion 2d (FIG. 3) of the fixing plate and by screws extending into holes 2e in the portion 2b of the plate. This manner of fixing is advantageous in that no lock-fixing screw shows or is accessible when the door is closed.

The housing 1 (FIG. 3) carries a vertical bolt 3 which has a chamfered portion and is biased downwardly by a `spring 4. The bolt can be actuated, in opposition to the action of the spring 4, by rotating a barrel 5 receiving a key 6 and provided with a lug 7 which extends into a recess 8 formed in this bolt. The latter co-operates with a keeper 9 which has a generally cylindrical shape `and a conical end portion 9b and is notched Aat 9a. This keeper extends through the aperture 2c into a cavity 10 formed in the lock housing 1.

This keeper is mounted to rotate about its axis in a bore 11 formed in the post M of the door frame in front of the aperture 2c of the fixing plate 2. The keeper is in axial alignment with a rod 12 which has a square cross-sectional shape and screwthreaded edges, the keeper being connected to this rod vby a sleeve 13 of plastic material such yas polyethylene. The sleeve 13 is secured to the keeper and the rod, for example by pins 13a.

Loca-ted at the outer end of the bore 11 is a guide and cover plate 14 which acts as a bearing for the keeper 9 and is secured to the outer wall of the post by screws 14a. Mounted at the inner end of the bore is a collar 1S having a tapped lbore 15a which `co-operates with the screw thread on the rod 12. The latter has such length as to be ladaptable on the thickest door. When the rod 12 is placed in such position that the keeper extends the required distance into the cavity 10, the collar 15 is screwed thereon so as to come slightly in contact with the inner w-all of the post M and is secured to this wall by screws 16. The rod 12 is then cut to the `desired length, there being provided sufficient length for positioning and fixing an arm or handle 17 which extends upwardly when the bolt co-operates with the notch 9a of the keeper, `as shown in FIG. 3. This handle has an aperture 17a of square cross-sectional shape in which the end of the rod 12 is engaged. An elastically yieldable washer 18 is interposed between the collar 15 rand the handle. The latter is locked in position on the rod 12 by a nut 19 .and a lock-nut 20 having a closed end. This arrangement permits the utilization of a standard assembly irrespective of the thickness of the post M, the sole adaptation consisting in cutting the rod 12 to the required length. The handle 17 carries at its end adjacent the `rod 12 a part-circular sector 21 (FIGS. 3 and 4) which cooperates with an abutment 22 formed on the collar 15 so as to limit the angular movement of the handle which is capable of moving from an upper vertical position for closing the door to a lower vertical position for opening the door, it rotating in the direction of arrow F (FIG. 4). For this direction of rotation of the handle, a left-hand screw thread is provided on the rod 12.

FIGS. 5, 6 and 7 shows a lock in accordance with another embodiment of the invention. This lock differs -from the lock described hereinbefore generally speaking only in the shape of the housing 1A (FIGS. 5 and 7) and in the shape of the fixing plate 2a (FIG. 6). It is of particular utility for very thick doors.

In this embodiment, the barrel, the outer end a of which is shown in FIG. 5, is located obliquely relative to the axis of the keeper.

The operation of the lock according to the invention will be explained with reference to the embodiment shown in FIGS. 1, 2, 3 and 4.

When the door is closed and the bolt 3 is engaged in the keeper 9, the door P can be opened in two ways:

(a) From the exterior, by introducing the key in the barrel 5 and rotating the latter so as to raise the bolt 3 in opposition to the action of the spring 4 'and release it from the keeper.

(b) From the interior, by rotating the arm or handle 17 in the direction of arrow F (FIG. 4) from its upper vertical position. The keeper 9 also rotates in moving slightly away from the bolt owing to the: screwing effect of the rod i2 in the collar 15 and this releases the bolt 3 by raising it and bringing the lower end thereof onto the unnotched cylindrical part of the keeper. The bolt is fully released from the notch of the keeper las soon as the handle reaches the horizontal position whereupon the door can be opened by merely pushing it.

If the handle remains in this position, it is nonetheless still possible to close the door again from the exterior but the bolt 3 now cannot engage in the notch of the keeper 9 and the door is not locked.

On the other hand, if the handle 17 is rst turned back to its upper vertical position and the door is subsequently pushed to its closed position, the chamfered portion of the bolt can slide on the conical end portion 9b of the keeper owing to the recess 8 and the bolt is thus urged upwardly and compresses the spring 4. When the door reaches its extreme closed position, the bolt is exactly in front of the notch 9a of the keeper into which it drops in locking the door. The latter can now only be opened from the exterior by means of the key.

It will be observed that a plastics sleeve 13 interrupts the thermic bridge that a continuous metal rod would form and thus insulates the interior of the coldroom from the exterior.

Although specific embodiments of the invention have been described, many modifications and changes may be made therein without departing from the scope of the invention as `defined in the appended claims.

Having now described my invention what I claim as new and desire to secure by Letters Patent is:

1. A safety lock structure for a door pivotably mounted in a door frame closing an enclosure, said lock structure comprising a support mounted on the door, a bolt reciprocably mounted on said support, a keeper rotatably mounted in the door frame, a handle connected to said keeper for rotating said keeper and located within said enclosure, said keeper comprising an elongated member having a notch which occupies a part of the cross-section of said member and is located in such position relative to said bolt as to be engaged by said bolt when locking the door to the door frame, the remaining part of said cross-section constituting a cam for moving the bolt out of the notch said bolt being mounted for movement away from said notch for unlocking the door from the door frame, yieldable means for biasing said bolt into said notch, a lock-operating device mounted on said support and means operatively connecting said device to said bolt for controlling the position of said bolt relative to said notch, lsaid means allowing movement of said bolt out of said notch when said device is in the position for locking the door to the door frame, whereby it is possible to unlock the door by rotating said handle from within said enclosure to cam said bolt out of said notch even when the door has been locked to the door frame by said lock-operating device.

2. A safety lock structure as claimed in claim 1, wherein said keeper is rotatably mounted in said door frame and said notch is moved away from said bolt and an unnotched part of said member placed in engagement with said bolt by rotating said keeper.

3. A safety lock structure as claimed in claim 2, wherein said keeper has a round cross-sectional shape and said notch has aradial extent not exceeding one half the diameter of the keeper.

4. A safety lock structure as claimed in claim 2, wherein the rod is connected to said handle at one end and connected to said member at the other end by a sleeve of plastics material which interrupts the thermic bridge between the interior of the enclosure and the exterior.

5. A safety lock structure as claimed in claim 2, wherein a rod comprising a screwthreaded portion on the end thereof is provided adjacent said handle, said lock structure further comprising a collar screwed on said screwthreaded portion and for fixing to the door frame between said handle and the door frame.

6. A safety lock structure las claimed in claim 5, wherein said rod has a square cross sectional shape and the edges thereof are screwthreaded.

7. A safety lock structure as claimed in claim 2, wherein said keeper has a -conical end for initially engaging said bolt before engagement of said bolt in said notch.

8. A safety lock structure as claimed in claim 1, wherein said support is a housing mounted on a fixing plate which is screwed to the door by screws which are hidden by the housing and inaccessible when the door is closed.

9. A safety lock structure as claimed in claim 8, wherein the housing is applied against both the outer face andthe edge of the door.

10. A safety lock structure as claimed in claim 8, wherein the housing is applied against the edge of the door.

References Cited UNITED STATES PATENTS 2,729,486 1/1956 Evans 292-92 2,762,645 9/ 1956 Bordner 292-92 X 2,855,771 10/1958 Berkowitz 292-92 X MARVIN A. CHAMPION, Primary Examiner. EDWARD J. McCARTHY, Assistant Examiner. 

